An interdisciplinary effort is proposed to develop high-data-rate digital microscopes for diagnostic work in the clinical pathology laboratory. Applications in clinical cancer cytology, tumor pathology, tumor therapy response predictive assays, and immunopathology require the high-resolution scanning of extended areas. Four projects are planned involving the Department of Pathology, the Optical Design Section, the Laser Physics Section, and the Microprocessor Section of the Optical Sciences Center, and faculty from the University of Heidelberg. The ultrafast laser scanner microscope will be taken into operation in clinical pathology, and operational software will be developed. A very-high-data-rate fluorescence scanner capable of recording 50,000 cells/minute, with novel optics optimized for high light collection will be designed. A module to measure low-light-level fluorescence and phosphorescence in cells and itissues at cryogenic temperatures will be designed. The multi-microprocessor system "Heidelberg POLYP" grant will be transferred into this program project. (3)